This is now the deadliest day for firefighters in this country since 9/11 and the pose shocking news in this state since the attack on congresswoman gabby giffords two years ago. Think of it, 92 firefighters here in prescott, one out of five of them, 20%, perished in one day, and these were the elite. In the army of firefighters battling wildfires in the west, these are the special forces. The granite mountain hot shots seen here in a training video. In a real fire this is exact same thing we would be doing. Reporter: Getting right into the thick of it. Digging the fire lines by hand, back-breaking work and practicing how to deploy their emergency shelters. 180 degrees. Reporter: Firefighters call these shake and bake tents. If you can't escape the fire, you shake it outnd then you bake in it until the fire passes. When we get out there, it's a completely different ball game. It's the real deal. We have to look out for each other. We have to have accountability. We have to trust each other. Reporter: Sunday was the first time the granite mountain hot shots ever had to deploy their shake and bakes. 19 of them died. The average age for the men in this crew, 22 years old. During fire season they're always ready to deploy at two hours' notice prepared to leave home for three weeks at a time. In fact, this crew had just gotten home from a new mexico wildfire when the call came out to come here. Any other job, you don't really have to worry about your life day in and day out but this job you have to watch your buddy too. You really end up creating a certain bond with certain people, relationships that last a long time. Reporter: It is just devastating. Prescott's hot shot crew has been around more than a decade, 1 of more than 100 of these scattered across the country, a brotherhood that is in mourning today.

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